Shortcuts for the "OCR Character" window is:
Expand selection: Alt + arrow right
Shrink selection: Alt + arrow left
Toggle italic: Ctrl+I (+ Alt+I depending on translation)
Toggle auto-submit-first-char: Alt+F (depending on translation)
Skip current letter(s): Esc (+ Alt+S depending on translation)
Skip entire subtitle: Ctrl+Shift+S (new shortcut)